SAP Message BCOMEC007 - The function is not possible for a call in status &1

Diagnosis
You tried to execute an action on a call in status '&V1&'. This is notpossible.
Further information on the external software component:
V3

Procedure for System Administration
The error can occur in 2 different places:
1. In the connected gateway
2. In the underlying CTI software
In this case the error occurred in (&V4&).
The return code for the underlying CTI software is: &V2&